1. Field of the Invention
The invention is related to the field of multiplexable optic fiber displacement, strain, acceleration, and pressure sensors and the multipoint sensing systems.
2. Description of the Prior Art
A sensor basically measures displacement and strain, but also measures other physical quantities such as acceleration and pressure upon minor modification of the sensor head.
The majority of optic fiber sensors developed in the prior art are of an intrinsic type which uses the optic fiber itself to measure a physical quantity by detecting the change in the properties of the light beam passing through the optic fiber. Because the properties of optic fiber are sensitive to many factors such as temperature and localized stress all long the fiber, the practical applications for intrinsic optical fiber sensors are limited to strictly controlled laboratory environments.
What is needed is an optic fiber sensor which is robust and can be used in real-world environments in which temperature and localized stresses occur along the fiber without loss of accuracy or precision of measurement.